Conclusion on the peer review of the pesticide risk assessment of the active substance halosulfuron (evaluated variant halosulfuron-methyl)

The conclusions of the European Food Safety Authority (EFSA) following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State Italy, for the pesticide active substance halosulfuron (evaluated variant halosulfuron-methyl) are reported. The context of the peer review was that required by Commission Regulation (EU) No 188/2011. The conclusions were reached on the basis of the evaluation of the representative use of halosulfuron-methyl as a herbicide on rice. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and literature in the dossier peer reviewed, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

© European Food Safety Authority, 2012

Halosulfuron is a new active substance for which in accordance with Article 6(2) of Council Directive 91/414/EEC Italy (hereinafter referred to as the ‗RMS‘) received an application from Nissan Chemical Europe SARL for approval. Complying with Article 6(3) of Directive 91/414/EEC, the completeness of the dossier was checked by the RMS. The European Commission recognised in principle the completeness of the dossier by Commission Decision 2006/586/EC.

The RMS provided its initial evaluation of the dossier on halosulfuron-methyl in the Draft Assessment Report (DAR), which was received by the EFSA on 30 March 2008. The peer review was initiated on 5 October 2011 by dispatching the DAR for consultation of the Member States and the applicant Nissan Chemical Europe SARL.

Following consideration of the comments received on the DAR, it was concluded that EFSA should conduct an expert consultation in the areas of mammalian toxicology and ecotoxicology and EFSA should adopt a conclusion on whether halosulfuron can be expected to meet the conditions provided for in Article 5 of Directive 91/414/EEC, in accordance with Article 8 of Commission Regulation (EU) No 188/2011.

The conclusions laid down in this report were reached on the basis of the evaluation of the representative use of halosulfuron-methyl as a herbicide on rice, as proposed by the applicant. Full details of the representative use can be found in Appendix A to this report.

No data gaps or areas of concern were identified in the section on identity, physical/chemical/technical properties and methods of analysis.

Data gaps were identified in the mammalian toxicology section to address the relevance of the impurities present in the technical specification and to clarify the potential genotoxic properties of the metabolite chlorosulfonamide acid in the context of consumer exposure of residues in food and groundwater relevance, the second of these leading to non finalised issues. A critical area of concern was identified since equivalence of the tested material with the technical specification was not demonstrated for the toxicity studies.

In the residue section the residue definition for risk assessment is only set provisionally, since the genotoxic potential of the major plant metabolite chlorosulfonamide acid is insufficiently addressed. Although residues in rice grains are very low, finalisation of the consumer risk assessment is pending a conclusion regarding the genotoxic potential of chlorosulfonamide acid.

The data available on environmental fate and behaviour are sufficient to carry out the required environmental exposure assessments at the EU level for the representative use, with the notable exception that information to estimate the potential for groundwater exposure by the metabolites ‗halosulfuron rearrangement‘ and chlorosulfonamide acid is not available. Consequently, the groundwater exposure assessments for these metabolites are not finalised.

Three data gaps were identified in the ecotoxicology section. Critical areas of concern were identified in the ecotoxicology sections regarding the high risk for non-target terrestrial plants and since equivalence of the tested material with the technical specification was not demonstrated for the ecotoxicity studies.

halosulfuron, halosulfuron-methyl, peer review, risk assessment, pesticide, herbicide